Stuttering is a speech-fluency disorder, in which sounds, syllables or words are repeated or produced longer than normal. It can also include interjections of sounds or words, and unduly prolonged pauses. These disfluencies cause a significant break in the flow of speech. About 5% of children, aged 2-5, will develop some stuttering during their childhood years. In approximately 20% of these children exhibiting developmental stuttering, the speech disorder sustains and might worsen with age. The underlying etiology of stuttering is unknown, and it is considered to be a combination of genetic and environmental factors. In some cases, stuttering may develop in relation to central nerve system injuries (e.g., stroke or traumatic brain injuries), and in rare cases it may be associated with emotional trauma. The disorder may have significant developmental, communicational, social and vocational impacts on the person-who-stutters.
While there is disagreement about acceptable treatment outcomes from stuttering therapy, many treatments have been developed for stuttering and have been successful to varying degrees, such as speech-therapy techniques and electronic fluency devices. Most of the stuttering-therapy devices typically focus on altered auditory feedback. One of such marketed devices is the SpeechEasy, which is a wearable device that can be used in everyday life. The SpeechEasy alters sounds that go through the device so that the user can hear his or her voice at a slight time delay and/or at a different pitch. The purpose of the delay and pitch change is to recreate a natural phenomenon known as the “choral effect”, which occurs while speaking or singing in unison with others, leading to a significant reduction or even elimination of stuttering. Other anti-stuttering devices provide visual alert for specific stuttering manifestations. However, the majority of these devices are not carried on human body. A tactile feedback prosthetic device, converting the stutterer's speech to vibrational signals is disclosed in U.S. application Ser. No. 289,766.
Conventional stuttering therapy anti-stuttering techniques are based on methods to regulate breathing and control the rate of speech, as stuttering is essentially a disorder manifested in poorly coordinated speech production muscles. Speech therapists equip their patients with various methods to attenuate their stutter. For example, one of the anti-stuttering techniques encompasses teaching the stutterers to speak in a mechanic shape, which usually enables a temporarily fluent speech. However, 84% of adults and teens reported experiencing a relapse after improving their fluency in therapy [NSA Survey Results 2009, web: 14 Sep. 2011, <http://www.westutter.org/stutteringInformation/NSA_Survey_Results.html>]. Six to twelve months (and sometimes more) are required for the people-who-stutter to practice this studied mechanic speech shape in order to achieve a permanently fluent and natural speech. The main challenge is in applying fluency methods continuously throughout the day and not only during clinical sessions or home training.
There is an unmet need for a device that can support the studied speech therapy techniques and accelerate the conversion of the achieved temporary fluency to a permanently fluent speech.